iOS 12.1 (build 16B92) is an official Apple over-the-air update for the iPhone 6s, released on 2018-10-30T17:17:00Z. The update package is 1.33 GB. This is a delta (partial) update that requires 11.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 4ccbba4081275ea6aa9821f7002cc3149b5e1611.zip.